Teaching aims：
1、知识目标：
(1) 词汇：require, fit, effect, thanks to, be sure about, at least, at the same time, say no to
(2) 句型: ①It's even thought that in the future more and more people will celebrate their hundredth birthday.
②Sure, it’s comfortable to sit on the couch and watch.
2、能力目标：从短文中获取关于身体健康的问题以及如何保持健康和安全生活的信息，写一篇如何保持健康的短文。
3、情感目标：养成健康的生活习惯，增强个人体质。
Teaching keys；
(1)句型：①Climbing may also mean falling—what goes up must come down.
②Yes, you knew I was going to say this!
